Wear-compensating pawl-and-ratchet mechanism.



J. SCHLAGEL.

WEAR COMPENSATING PAWL AND RATCHET MECHANISM.

APPLICATION FILED JUNE 27. i913.

1,220,564. Patented Mar. 27, 1917.

' 3 WITNESSES l/VVE/VTOR 4 ATTORNEY UNITED @TATES PATENT @EFlltlfi.

JACOB SOI-ILAGEL, OF BROOKLYN, NEW YORK, ASSIGNOR T0 CONRAD HUBERT, OFNEU YORK N. Y.

' WEAR-OOMPENSATING PAWL-AND-RATCHET MECHANISM.

and useful Improvement in Wear-Compensating Pawl-and- Ratchet Mechanism,of which the following is a specification, reference being had therein 0the accompanying drawings forming part thereof.

My invention relates in a general way to wear compensators orself-adjusting devices for the operating connections of frictionalrestraining or looking devices such as brakes or clutches. Moreparticularly, my invention is a self-adjusting pedal connection forspring operated engine starters. Examples of engine starters to which myinvention is .tion, is released. as

applicable are he subject of patents to Clyde J. Coleman, N o. 867 ,795,0f October 8, 1907, No. 1,056,972, of March 25, 1913, and No.1,102,322, of July 7, 1914.

' 11 these engine starters, starter engine, I spring-pressed to engagingor gripping posiby pressing a pedal. It has been found that wear at thebrake shoe raws upon the brake-releasing connection such as the flexibleconnectors 70 and 21, re-

spectively, in the above mentioned first two patents, and such drawingcauses the operatmg pedal to project to the inside of the car more andmore as the wear goes on, and excessive projection of the pedal isundesirable. Also when the pedal has reached the limit of the projectingmovement permitted or possible, the brake band of the starter can nolonger be seated to lock the starter spring.

The object of the present invention is to overcome the above mentioneddifficulty due to wear at the brake band and also to automaticallycompensate for any stretching which may take place in the flexiblebrakeor cable, should it stretch by reason of use.

I shall now describe the self-adjusting brake operating device embodyingmy invention illustrated in the accompanying drawings and shallthereafter point out my invention in claims.

Specification of Letters Patent. Application filed June 27, 1913.

Patented Mar. 27, 1917.

Serial No. 776,112.

Figure 1 is a side elevation, partly in section, of the complete device.

Fig. 2 is an enlarged vertical section on a plane indicated by the line2-2 of Fig. l as viewed from the right.

Fig. 3 is a vertical section to Fig. 1 on a plane indicated by the line3-3 of Fig. 9 as viewed from the right, the parts appearing in adifferent relative position and as seen from the rear in Fig. 1.

*ig. 1 is a rear elevation, partly in secti on, on a reduced scale of aspring engine starter illustrating the application of my invention.

In the construction illustrated in the drawings, flexible connector orthe scale of a brake-releasing cable 1, shown as led Sheath 2, isanchored to a brake controlling disk or drum 3, as by means of an anchorpin 4, and is wound peripherally around a circular shoulder forming awinding space on the disk 3 and from which the cable 1 eX- tendstangentially.

he cable extending from the disk 3 is connected to a brake lever 5 of aspring-operated engine starter (Fig. 4). A spring 6, connected with thelever 5, holds a brake 7, connected with the lever 5 by'a chain 8,normally in action on a brake wheel or spring-locking disk 9. Drawingupon the cable 1 will release the brake and permit the starter spring toeffect an engine-starting operation, and relief of restraint on thecable will permit the spring 6 to lock the starter spring. Any desiredfurther information as to the engine starter may be obtained from theabove mentioned patents.

Radially outward from the cable-receiving space the disk 3 is providedwith peripheral ratchet teeth shown as sloping on one side The disk 3 issupporting stud 10 bracket 11 the car and through a protective lower endof the stem of apedal 17 .11 and shown as the brake-releasing cable 1under the influence of the brake-applying spring, such Thebrake-releasing operation is effected through the ratchet teeth of thedisk 3 by means of a spring-pressed pawl 14 pivoted at an intermediatepoi t on a bent lever 15,, the latter being fulcrumed on the stud 10outward from the star spring 13 and also outward from an intermediatecollar or washer 16. The free end of the brake-releasing lever 15 ispivotally connected to the guided floor of the car so that the pedalnormally projects a suitable distance above the floor, as appears inFig. 1. The lever 15, carrying the pawl 14c and the pedal 17, isreturned to normal position after each actuation or forward movement, bymeans of a retractile coiled spring 18 anchored to a lug on thesupporting bracket attached to the lever 15 between the pivot stud 10and the pawl 14.

Normally the pawl M is held out of engagement with the ratchet teeth ofthe disk 3 (Figs. 1 and 2) by means of a projecting cam lug, shown asprovided at the upper end of the pawl 14, coming into contact with acam-actuating surface provided on the contiguous portion of thesupporting bracket 11. However, when the pedal 17 is depressed (Fig. 3),imparting a forward or downward movement to the lever 15, the awl 14:will come into engagement with the ratchet teeth of the disk 3, therebyrotating the disk 3 (Fig. 3) and drawing on the cable 1 to release thestarter brake for effecting an engine-starting operation.

When the pedal 17 is released, the return spring 18 will restore thelever 15, pedal 17 and pawl 14' to the position shown in Figs. 1 and 2,the pawl 14 being thrown out of engagement with the ratchet teeth of thedisk 3, permitting this disk to continue to rotate under the stressexerted upon the cable 1 by the starter brake-applying spring, such as6, until the brake band is firmly seated, regardless of any wear uponthe latter or upon the braking surface of the spring-locking disk. Whenthe wear upon the starter brake has become sufficient to thus move thedisk ratchet tooth, the pawl 14 will then engage the next followingtooth in the brake-releasing operation, and so on. The wear of thestarter brake is thus compensated for and the pedal 17 will alwaysproject to the same extent within the car. The return spring 18 may beomitted if the brake-applying spring 6 be made sufliciently strong toreturn the ratchet and lift the pedal lever 15. Then when the brake wearhas become sufiicient,

in an opening in the this return movement will engage the heel or camlug of the pawl 14; with the surface of Fig. 1, that the stem 3 adistance equal to one.

and permit the pedal lever to drop slightly until the pawl is seatedagainst the next f tooth below. a

The wearing of the braking surfaces is what has given trouble prior tothis invention, but, on the other hand, should the cable 1 stretch byuse'to a greater extent than the wear of the brake, my inventionwillcompensate also for this stretching of the cable. In that case thestretched cable'will fail'to return the disk 3 to itsinitial positionand the pawl 14: will to that extent ride over the ratchet teeth in thefinal portion of the return movement of the lever 15. cable hasstretched to the extent of one ratchet tooth, the pawl will engage thenext tooth in advance, and so on.

It is to be noted, as clearly appears in of the pedal 17 is made in twoloosely telescoping parts, permitting the upper projecting pedal part tobe readily removed and carried away by the chauffeur, to preventtampering.

It is obvious that various modifications may be made in the constructionshown in the drawings and above particularly described within theprinciple and scope of my invention.

I claim z- 1. A self-adjusting brake-releasing pawl and ratchetmechanism for brakes having a normal tendency to the applied condition,such mechanism comprising a pawl. two relatively movable parts one ofwhich carries the pawl and the other of which is a ratchet cooperativewith the pawl, one of the said parts being part adapted to be connectedto the brake to release the same and to be returned by the brake to thenormal position and the other of the said parts being an operatingmember for the. pawl and ratchet, means operative to disengage the pawland ratchet upon the return of the operating member to a predeterminednormal position, an yieldable movement-restraining means for thebrake-controlling part for stopping and holding such part in correctadjusted position relatively to theoperating member in the normalposition of the latter.

2. A self-adjusting brake-releasingpawl for brakes having and ratchetmechanism a normal tendency to the applied condition,

the brake to the normal position and the other of the said parts beingan operating.

member for the pawl andratchet, position- When the a brake-controllin grestoring means for the operating member for returning the latter to apredetermined normal position, means operative to disengage the pawl andratchet upon the return the operating member to the normal position bythe position restoring means, and frictional stopping and holding meansengaging the brake-controlling part for automatically adjusting thenormal position of such part relatively to the normal position of theoperating member.

3. A self-adjusting brake-releasing pawl and ratchet mechanism forbrakes having a normal tendency to the applied position, such mechanismcomprising a brake-controlling drum disk provided with ratchet teeth andhaving a peripheral winding space providing for flexibly connecting thebrake-controlling drum to a brake for releasing the brake, a frictionstop for yieldingly holding the disk at the position to which it isreturned by the applied brake, a disk-operating manual lever pivoted concentrically with the disk, a pawl carried by the lever and engageablewith the ratchet teeth of the disk to operate the brake during theforward movement of the lever, an abutment adapted to effect thedisengagement of the pawl upon the the reverse or return movement of thelever der continued stress of the brake as the rake moves to the applledposition until such disk is stopped by the friction stop at the correctadjusted position relatively to Copies of this patent may be obtainedfor five cents each, by Washington, D. G.

the pawl carried by the operating lever in the returned position of thelatter and a spring arranged to effect the return movement of the lever.

4. Brake mechanism comprising a brakeand brake-releasing meansincluding: an operative member adapted to receive operative energy, anoperated member connected with the brake, means for maintaining a fixedconnection between the operative and operated members during theactuation of he operative member in one direction to release the brakeand during a reverse movement of both members as the brake isbrake-setting movement.

5. Brake mechanism comprising a brake and brake-releasing meansincluding: a manually operative member, a ratchet connected with thebrake, a pawl carried by the manually operative member and arranged tomaintain connectlon with a single tooth of the ratchet during itsactuation of the ratchet to release the brake and during the reversebrake-setting movement, and a detent arranged to disconnect the pawlfrom said tooth at the end of said reverse or brake-setting movement.

In testimony whereof I have afiiXed my signature in presence of twowitnesses.

JACOB SCHLAGEL. Witnesses HARRY G. Lewis, JOSEPH T. LEYDEN.

addressing the Commissioner of Patents

